This story is part of The Salt Lake Tribune’s ongoing commitment to finding solutions to Utah’s biggest challenges through the work of the Innovation Lab.
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The solution may lie beneath our feet.
There is something deceptively simple about geothermal energy. The crushing gravity compresses the earth to the point where its molten metal center is 9,000 degrees Fahrenheit. Even thousands of kilometers near the surface, the temperature is still hundreds of degrees.
In some places, this heat reaches the surface, either as lava flowing through volcanic vents or as steaming water bubbling up in hot springs. In these places, people have been using geothermal energy since the beginning of time.
But what if we could drill into the rock and essentially create our own hot spring? That’s the idea behind “extended geothermal systems,” and the most promising such effort in the world is taking place in Beaver County.
The site called Utah FORGE (Frontier Observatory for Geothermal Research) 10 miles north of Milford is little more than a drill site and a few buildings on Utah School and Institutional Trust Lands Administration land. But it is the US Department of Energy’s lead laboratory for advanced geothermal research, and the University of Utah is the scientific overseer. Seven years ago, the U. of U. proposal beat three of the DOE’s own national laboratories in a national competition.
“When you need to select the best area in the country to build an EGS facility, you will be driven to Milford. The DOE recognized this in 2015,” said Joseph N. Moore, professor of civil and environmental engineering at the University of Utah and lead investigator for Utah FORGE.
Among the advantages:
– It is in a known area of thermal activity. Roosevelt Hot Springs is nearby, and a small nearby geothermal plant has been generating electricity for about 30,000 homes for years.
– It has hundreds of cubic miles of hot granite below the surface through which no water flows.
– There is accessible water that cannot be used for drinking or agriculture because it contains too many naturally occurring minerals. But this water can be used to extract heat from underground.
– It has access to transmission lines. Beaver County is home to a growing amount of wind and solar energy, making it easier to access to consumers.
DOE has invested $50 million in FORGE and is now adding an additional $44 million in research funding. The U. of U. solicits suggestions from scientists.
“These new investments in FORGE, the flagship of our EGS research, can help us find the most innovative and cost-effective solutions and accelerate our work towards large-scale geothermal deployment and support President Biden’s ambitious climate goals,” said Secretary of Energy Jennifer Granholm.
The idea is to drill two deep wells more than a mile deep in solid granite that registers about 400 degrees. Then cold water is pumped into one well to allow hot water to be drawn through the second well. One of these wells has been drilled and the second is planned for next year.
But if it’s solid rock, how does the water get from one well to another? Scientists have turned to a technology that has transformed the oil and gas industry: hydraulic fracturing, also known as “fracking.” They pump water down at extremely high pressure to create or widen small cracks in the rock, and these cracks allow the cold water to flow over the hot rock to the second well. They have done some hydraulic fracking work from the first well.
Moore is quick to point out that using a geothermal energy fracking process doesn’t create the environmental problems associated with oil and gas fracking, primarily because it doesn’t produce dirty effluent and gases. In addition, the oil released when fracturing can lubricate underground faults, and the removal of oil and gas creates gaps, both of which lead to more and larger earthquakes.
Fracturing in enhanced geothermal heat creates seismic activity that seismologists are closely monitoring, Moore said, but the circumstances are quite different. With geothermal fracking, there is only water that can be returned to the ground without contamination. And creating fractures in an isolated piece of granite is less likely to affect faults. The hope, he said, is that once there are enough cracks for sufficient flow from one pipe to another, it can continuously produce hot water without further breaking.
And it never goes out. Moore said that as little as 2% of the available geothermal energy in the United States would be enough to power the nation alone.
This next round of $44 million in federal funding is about taking that oil and gas process and making it specific for enhanced geothermal energy. This includes further seismic surveys and the search for the best “propellant” – the material used to keep the fracture open. Oil and gas use fracked sand to keep the fractures open, and geothermal’s higher temperatures make this a challenge.
“FORGE is a derisking lab,” Moore said, meaning that the federally funded scientists at the U. of U. are doing some work to turn the theory of EGS into a practical clean energy solution. He said it costs $70,000 a day to drill wells that deep. They drill 10 to 13 feet an hour, and it takes six hours just to pull out a auger to change augers, which they do every 50 hours. This early, expensive work makes it easier for private companies to turn the technology into a commercially viable business. Moore said all research is in the public domain.
According to Moore, FORGE doesn’t currently employ many full-time employees in Beaver County, but it has used local contractors for much of the work and has filled the county’s hotel rooms for occasional meetings. High school students were also hired to help manage core samples from the deep wells.
“They have worked really well with the city,” said Milford Mayor Nolan Davis. Moore and others have regularly made presentations to his city council and sponsored high school competitions to teach students about geothermal energy. People in the city, Davis said, are aware that the world is watching Utah FORGE, and there is hope that geothermal energy will gain a greater presence as and when commercial development begins. “We’re hoping they can come in and maybe build several small power plants.”
Davis also noted that Beaver County’s solar and wind power generation has already been contracted to California. “We want to get some power that we can keep in the county.”
Tim Fitzpatrick is a renewable energy reporter for The Salt Lake Tribune, a position funded by a grant from Rocky Mountain Power. The Tribune retains overall control of editorial decisions independent of Rocky Mountain Power.
https://www.sltrib.com/renewable-energy/2022/09/30/is-future-energy-sitting-below/ Does the future of energy sit beneath this small Utah town?